1. Field of the Invention
This invention relates to an image data generating method and apparatus for generating data of a parallax image string used for generating a holographic stereogram. This invention also relates to an image data converting method and apparatus for processing data of a parallax image string with viewing point conversion to generate data of a new parallax data. This invention also relates to a method and apparatus for generating a holographic stereogram based on data of the parallax image string. This invention also relates to a recording medium having stored therein data of the parallax image string used for generating a holographic stereogram. This invention similarly relates to a method for transmitting data of the parallax image string used for formulating a holographic stereogram.
2. Description of the Related Art
A holographic stereogram is prepared by sequentially recording a large number of images, as original images, on a sole recording medium for hologram as a strip-shaped or dot-shaped element hologram. These images have been obtained by sequentially imaging an object from different viewing points.
As shown in FIG. 1, in generating a holographic stereogram having the parallax information only in the transverse direction, an object 100 is sequentially imaged from different viewing points of the transverse direction to produce a parallax image string 101 made up of plural images having the parallax information only in the transverse direction. The images 102 making up the parallax image string 101 are sequentially recorded as strip-shaped elementary holograms on a recording medium for hologram 103 so that these images 102 will be consecutive to one another in the transverse direction. This yields a holographic stereogram carrying the parallax information in the transverse direction.
In this holographic stereogram, in which the information of the plural images 102, obtained by sequentially imaging the object from plural viewing points of the transverse direction, is sequentially recorded as strip-shaped elementary holograms so that the images 102 will be consecutive to one another, two-dimensional images, as viewed by left and right eyes, differ from each other if this holographic stereogram is viewed by a viewer with both eyes. This causes the viewer to perceive the parallax so that a three-dimensional image is reproduced.
As shown in FIG. 2, the string of parallax images, from which the holographic stereogram is derived, is produced by translating a camera 104 directed to the object 100, as the camera 104 is oriented in a fixed direction, and by imaging the object 100 a large number of times. That is, the camera 104, oriented towards the object 100, is translated from a position in which the object 100 enters an imaging range by the camera 104, to a position in which the object 100 is moved out of the imaging range by the camera 104, and by imaging the object a large number of times during this time interval, whereby a parallax image string, from which is originated the holographic stereogram, is produced. Meanwhile, this system of translating the camera 104 as the latter is kept in a fixed direction is termed a straight track system.
It is noted that, in a holographic stereogram, the relative position between the viewing point of the camera 104 and the object 100 at the time of imaging is kept in the reproduced image of the generated hologram as well. As shown in FIG. 3, if the parallax image string, produced as described above, is directly used for generating a holographic stereogram, a reproduced image Z is formed at a more recessed position than the hologram plane Ha of the holographic stereogram H. Therefore, with this holographic stereogram, a reproduced image Z is distorted or blurred, unless a viewer sees the reproduced image Z, with the viewing point S set on the hologram plane Ha, so that the distance d0 between the reproduced image Z and the reproduced image Z of the viewer coincides with the distance d between the object 100 and a viewing point of the camera 104 at the time of imaging.
Thus, for dissolving this problem in the preparation of the holographic stereogram, it is necessary to perform viewing point conversion processing on data of the original parallax image string so that the reproduced image Z will be formed in the vicinity of the hologram plane Ha of the holographic stereogram H, as shown in FIG. 4. By this viewing point converting processing, the reproduced image Z is free of distortion or blurring even if the viewing point S is set at a position remote from the hologram plane Ha.
In our Japanese Patent Application H-8-170018, corresponding to Japanese Laid-Open Patent H-10-20754, the present Assignee has proposed a system of performing viewing point conversion processing on data of the parallax image string to generate a holographic stereogram. In this system, an object is imaged from different viewing points to prepare data of a parallax image string, this data of the parallax image string is processed with viewing point conversion and the resulting converted data is used to generate a holographic stereogram.
This system, however, tends to be bulky on a whole since it is made up of a mechanism for generating data of a parallax image string, a mechanism for viewing point conversion processing and a mechanism for generating the holographic stereogram.
It is therefore an object of the present invention to provide a system for performing viewing point conversion on data of a parallax image string made up of plural images having the parallax information, such as the system for generating a holographic stereogram, in which a mechanism for generating the data of the parallax image string can be independent from other mechanisms.
In one aspect, the present invention provides an image data processing system including means for formulating images having parallax data, made up of a plurality of images of an object from different viewing points, and data attachment means for attaching the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data.
In another aspect, the present invention provides a method for processing image data including generating images having parallax data, made up of a plurality of images of an object from different viewing points, and attaching the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data to the images having parallax data.
In still another aspect, the present invention provides an image data converting system including data receiving means for receiving images having parallax data, made up of a plurality of images of an object from different viewing points, and the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data, and viewing point conversion means for performing viewing point conversion processing, on the basis of the information, on the images having parallax data, as received from the data receiving means.
In still another aspect, the present invention provides an image data converting method including inputting images having parallax data, made up of a plurality of images of an object from different viewing points, and the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data, to computing processing means, and performing viewing point conversion processing, on the basis of the information, on the images having parallax data.
In still another aspect, the present invention provides a holographic stereogram printing system including data receiving means for receiving images having parallax data, made up of a plurality of images of an object from different viewing points, and the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data, and viewing point conversion means for performing viewing point conversion processing, on the basis of the information, on the images having parallax data, as received from the data receiving means, and means for generating a holographic stereogram using new images having parallax data, as obtained on executing viewing point conversion processing by the viewing point conversion means.
In still another aspect, the present invention provides a method for generating a holographic stereogram including inputting images having parallax data, made up of a plurality of images of an object from different viewing points, and the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data, to computing processing means, performing viewing point conversion processing, on the basis of the information, on the images having parallax data, by the computing processing means, to produce new images having parallax data, and using the new images having parallax data for generating a holographic stereogram.
In still another aspect, the present invention provides a computer-readable recording medium in which there are stored images having parallax data, made up of plural images of an object from different viewing points, and data required for executing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data.
In yet another aspect, the present invention provides a data transmission method including collectively transmitting images having parallax data, made up of a plurality of images of an object from different viewing points, and the information necessary for performing the viewing point conversion processing of converting the viewing points for the object on the images having parallax data.
According to the present invention, as described above, it is possible, in a system in which images having parallax data, and which are made up of plural images having the parallax information, are processed with viewing point conversion, and the resulting new images having parallax data are used, as in a system of generating a holographic stereogram, to provide a unit for generating data of a parallax image string independently of other unit or units.
Thus, according to the present invention, a studio for imaging a parallax image string, a data processing center for viewing point conversion and a printing laboratory for generating a holographic stereogram may be provided independently of one another.